Final answer:
Earl W. Sutherland discovered cyclic adenosine monophosphate (cAMP) as a second messenger in hormone action, highlighting how hormones like adrenaline affect cells through cAMP activation.
Step-by-step explanation:
Earl W. Sutherland, a prominent biochemist, is recognized for his discovery of cyclic adenosine monophosphate (cAMP) as a second messenger in the action of hormones. This groundbreaking work on the mechanisms of hormone action was instrumental in understanding how hormones like adrenaline affect cells. Specifically, he discovered that hormones can induce the formation of cAMP, which, in turn, activates other enzymes within the cell to elicit responses. Sutherland's contributions were significant, earning him the Nobel Prize in Physiology or Medicine in 1971.